This question asks for evidence of creative problem-solving under real constraints, not just applying a textbook fix.
Key Points: • Describe the constraint that ruled out the obvious solution (cost, time, infrastructure limits). • Explain the alternative approach you chose and why it was a better fit. • Quantify the impact wherever possible. • Highlight the reasoning process, since that's what interviewers are really probing.
Example: Facing performance bottlenecks, instead of scaling up hardware, an engineer might introduce a caching layer that cuts server load significantly without added infrastructure cost.
Interview Tip: A concise interview answer is:
"When we hit severe performance bottlenecks, rather than just throwing more hardware at the problem, I introduced a caching mechanism that improved response times and cut server load by about 70 percent with no additional infrastructure cost. It was a case of solving the root cause instead of masking the symptom."